Wellhead sealing arrangement



Jan. l5, 1952 M, T, WORKS 2,582,518

WELLHEAD SEALING ARRANGEMENT Filed Jan. 3, 1947 MADDEN T. WORKS INVEN TOR.

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ATTORNEYS Patented Jan. 15, 1.952

vMadden 'r. Works-moesten, Vriferi.,assigner to GameronlflronWorks, Houston, Tex., afcorporationv of Texas Application lJanuary 3, 1947,.,seria1'No- 720,005

, l This invention relates in'y general to seal forming combinations and has for its general `object be suited for use in sealingbetween a well casing and a casinghead tubing headc'ombination surrounding same.

`More specifically it isan object of this invention to provide a seal forming means vfor sealing [between a well headand an inner'pipeand'to'provide means invconnection therewithwhich will make it vpossible to -e'ffect'theseal required'after the well head or other equipment has been installed.

Another objectofthis invention is toprovide aseal forming means-which maybe mounted in the tubing Vhead or other-equipment on top of the casing head 'and which will not require any "8 Claims. (Cl.:285-22) rthe provision of such a` combination which will I specialconstruction of the casing head.` In ythis connection it is to be understood that throughout thespecication and claims-reference t'o a ltubing head is intended to include -either aitubing head or other equipment which may be placed uponA a casing head.

vAnother object'of this invention is to provide a seal of the character referred to IWhich maybe tightened and rendered effective by means of Vhydraulic pressure after the apparatus has-been fully assembled.

Anotl-ier-object of this invention i'sto provide a seal of the character referred toxin combina- 'ltion vwith inearis foi-"holding the seal `reffective even though fthe v'pressure which was appliedfto renderr it elfective should bereleased. Other 'objects and 'advantages of this invention willwbecomel apparent from the following vde'- scription 'taken vin connection with-theaccompanying drawingswherein isset forth by' way of `illustration and example twoembodiments of the invention. w

In the drawings: I Fig. 1 is a fragmentary view partly in side ele- ;vation and partly'in'vertical vcrosssection illustrating a portion of a casing head,.a tubing head and a casingY together with a'seal forming apparatus constructed in accordance with this invention.

Fig.v 2uis a view corresponding .toa portion of .that part of'Fig. 1 `which .is shown in cross section and illustrating a slightlymodied form `of the invention. a

The'illustration in the drawingin Fig. lfshows the upper end portion ofthe` usual casing head I having an outwardly extending flange `2 with openings 3 therethrough-for the reception-ofthe studsl. This casing head "I is Aprovided withy a tapered .innersurface 5 customarily referred to as a slip bowladapted to'receive tapered vslips 6 having upwardly directed gripping .teethV 'I i-on their inner surfaces for the purpose of gripping `and lsuspending the casing 8 that `extends up through the casing head and into the apparatus above the casing head.

The ystrlmture thus far'described is conventional.

Secured to the upper flange 2 of the casing head by means of the studs II is the flange 9 of the tubing head or other well head apparatus I, the flanged having openings- I'I therethrough for the reception of the studsd.

`The adjacent surfaces of theiianges 2 and :59 have formed therein opposed sealing ringreceiv- -ing grooves I2 and I 3'respectively, and mounted in 'these -grooves is a sealing ring Illvwhich provides a seal between the casing head and tubing headv or' the like;

In order to provide thenecessary seal between -theupper end ofthe casing and the interior of the casing head, tubing head combination, thetubing 'head' is' in this instance provided lwith a counterbore I5 and with a passageway IS leadingfrom the counterbore adjacent theupperend thereof outwardlythrough the wall of the tubing 'head-and threaded adjacent its outer end to re- "ceive a pressure retaining check valve fitting Il -V olf' fanyf suitable well known construction.

Adj acent its upper end this" counterbore is pro- `videdwith smooth Walls and there is located at its upper end a lip-type or other suitabletype of -sealingririg I`8, whilespaced therefrom and on Atl-ie opposite side of the opening from the passafgewayl I6" is a second inverted sealingring vI9 sirnilarin all'respects to thefring I8. A follower ring 20 having its larger portion of an oute'r diameterrto' twithin the smaller portion of the 'bore of the tubing head and a laterally extendin'gfange 2I having'an outer diameter adapted to fit within the counterbore I5 is placed in the counterbore following the ring I9. It will be seen fromithe'drawing that'the main body portion of this ring taken with the flange 2I provides a closed annular `receptacle for `thereceptionof pressure uid Iforced into the counterbore through the tting -Il and thepassa-geway I6, and that forcing such fluid into the counterbore will cause the followerring 2D to move downwardly with respectV to the tubingl head.

The following ringi! isalsoprovided witha larger portion -22 of an inner diameter large enough to receive the upper endof the casing '8 and with an overhanging lip `23 adapted to overhang 'the upper end of the casing 8 and limitlthe downwardmovement ofthe follower `ring "210. vFrom the overhanging lip 23 to its upper end vthe 'follower ring -20 ispreferably flared outwardlylto provide a guide for tubing or other apparatus to-lvbe la'ter inserted into vthe well.

3 Below the follower ring 20 there is inserted in the counterbore a split ring 24 forming a packing ram and being tapered at its lower end as shown at 25 to more eifectively expand the annular packing body 26 which is inserted into the counterbore below the ram 24. This ring 24 is split at 2'I and is provided on its outermost surface with upwardly directed ratchet teeth 28 tting into corresponding ratchet grooves formed in the wall of the counterbore I intermediate the ends of the counterbore. It will be seen that this construction will permit the ring 24 to be forced downwardly by the follower 20, but that due to the fact that the ring 24 is given a set which makes it normally of larger diameter than the counterbore, it will expand until its ratchet teeth 28 are engaged with the corresponding grooves in the counterbore thus providing a mechanical detent which will prevent its retrograde or upward movement away from the packing body 26.

The packing body 26 is supported by a support ring 29 which is tapered on its upper end at 30 in the same manner as the ram 24, and is adapted to rest at its lower end 3| upon the upper ends of the slips 6.

It will be seen that in operation after the casing has been hung in the casing head in the usual manner and severed at a desired distance above the casing head, the rings I8 and I9 may be placed in the counterbore I5 together with the follower ring 20, the ram 24, the packing body7 26 and the support ring 29, and that this assembly may then be placed on the upper end of the casing head with the sealing ring I4 in place in the grooves I2 and I3, and secured to the casing head by means of the studs 4.

In order to provide the necessary seal between the casing head, tubing head combination, it is thereupon necessary only to attach a source of hydraulic pressure to the valved fitting I1 and force a pressure fluid into the counterbore between the rings I8 and I9 and around the outside of the follower 20. This hydraulic pressure will move the follower 20 downwardly and serve as an actuator for the ram 24 and packing body 26, forcing the ram 24 against the packing body 26 and causing the same to expand laterally into sealing engagement both with the casing 8 and with the wall of the counterbore in thev tubing head ID. It will be understood that the necessary degree of sealing may be effected by the amount of pressure fluid and the pressure of the iiuid injected through the bore I6. The packing body 26 will of course be made of a material iiowable under pressure so that when the pressure is thus applied to it it will be compressed endwise and caused to expand laterally to provide the necessary seal.

It will further be seen that the interengagement of the ratchet teeth 28 on the ram 24 with the grooves formed in the inner surface of the counterbore will provide a mechanical detent preventing the retrograde movement of this ram away from the packing once the packing has been compressed by movement of the ram. This is of importance in that if the fitting I'I should become ineffective for any reason or should be knocked off, thereby releasing the pressure acting upon the follower 2U, the ram 24 would not be allowed to move upwardly and release the pressure on the packing body 26. Therefore, the seal about the casing within the tubing head would remain effective even though the hydraulic 4 pressure which rendered it effective in the rst place should be released.

Referring now more particularly to Fig. 2, the parts are identical with those illustrated in Fig. 1 having corresponding. numbers except for the fact that the counterbore I5a in the tubing head is not provided with the grooves illustrated in the form shown in Fig. 1 but has a smooth wall throughout, and the ram 24a is not provided with teeth such as the teeth 28 on the ram 24. Instead, there is interposed between the ram 24a and the follower 20 a pair of split co-acting wedge shaped rings 32 and 33 respectively. The ring 32 has upwardly directed teeth 34 in engagement with the casing and the ring 33 has similar upwardly directed teeth 35 in eng-agement with the inner wall of the counterbore. These two rings are so arranged that a downward movement of the ring 32 or an upward movement of the ring 33 will tend to wedge them between the casing and the inner Wall of the counterbore. However, due to the fact that the teeth 34 and 35 are all directed upwardly, pressure exerted by the follower 20 against the ring 32 will cause downward movement of both rings and corresponding downward movement of the ram 24a resulting in the expansion of the packing. But when there is any tendency for the ram 24a to move upwardly, this will be opposed by both sets of teeth 34 and 35 and the rings will wedge against each other between the casing and the wall of the counterbore so that substantial upward movement of the ram 24a will be prevented.

This provides a mechanical detent having much the same effect as that illustrated in Fig. 1, but having the advantage that less retrograde movement of the ram is permitted before it is stopped all together because the teeth 34 and 35 may grip the casing and the tubing head 'at any point, and the additional advantage that it is unnecessary to form grooves in the wall of the counterbore.

From the foregoing, it will be appreciated that a device has been provided which is capable of carrying out and accomplishing al1 of the objects and advantages sought by this invention.

Having described my invention, I claim:

1. A seal assembly comprising in combination with an annular deformable packing body, a ring movable against said body in an endwise direction to cause said body to expand laterally, a hydraulic actuator for moving said ring in such direction, and a mechanical retainer for holding said ring against retrograde movementto maintain pressure on said packing body once the same has been applied.

2. In combination with two spaced members one of which is located within the other, the other of said members being counterbored, an annular packing body within said counterbore and surrounding the other member, an annular ram within said counterbore and movable to apply pressure endwise against said packing body to cause the same to expand laterally and form a seal between said members, a hydraulic actuator for moving said ram toward said packing body, and a detent for holding said annular ram against retrograde movement in a direction away from said packing body.

3. In combination with a well casing, casing head and tubing head in which the casing head land tubing head are secured and sealed to each other and surround the upper end of said casing in spaced relation thereto and said tubing head is provided with a counterbore extending upwardly from its lower end and surrounding said casing, an annular packing body within said counter- :bore and surrounding said casing, a support ring extending upwardly from within said casing head and engaging said packing body to support the same against downward movement, an annular ram above said packing body and movable downwardly to apply pressure thereto and cause the same to expand laterally into sealing engagement with said casing and tubing head, a detent for holding said ram against retrograde movement away from said packing body, and a hydraulic actuator for moving said ram toward said packing body to compress the same.

4. In combination with a well casing, casing head and tubing head in which the casing head and tubing head are secured and sealed to each other and surround the upper end of said casing in spaced relation thereto and said tubing head is provided with a counterbore surrounding said casing, an annular packing body within said counterbore and surrounding said casing, a support ring engaging said packing body to support the same against movement, an annular ram on the other side of said packing body from said support ring and movable to apply pressure thereto and cause the same to expand laterally into sealing engagement with said casing and tubing head, a detent for holding said ram against retrograde movement away from said packing body, and a hydraulic actuator for moving said ram against said packing body to compress the same.

5. In combination with a well casing, casing head and tubing head in which the casing head and -tubing head are secured and sealed to each other and surround the upper end of said casing in spaced relation thereto and said tubing head is provided with a counterbore extending upwardly from its lower end and surrounding said casing, an annular packing body within said counterbore and surrounding said casing, a support ring extending upwardly from within said casing head and engaging said packing body to support the same against downward movement, an annular ram above said packing body and movable downwardly to apply pressure thereto and cause the same to expand laterally into sealing engagement with said casing and tubing head, a detent for holding said ram against retrograde movement away from said packing body, and a hydraulic actuator within said counterbore above said ram for moving said ram downwardly against said packing body to compress the same, said tubing head having a passageway therethrough from its exterior to said hydraulic actuator whereby hydraulic uid under pressure may be supplied to said actuator.

6. In combination with a well casing, casing head and tubing head in which the casing head and tubing head are secured and sealed to each other and surround the upper end of said casing in spaced relation thereto and said tubing head is provided with a counterbore extending upwardly from its lower end and surrounding said casing, an annular packing body within said counterbore and surrounding said casing, a support ring extending upwardly from within said casing head and engaging said packing body to support the same against downward movement, an annular ram above said packing body and movable downwardly to apply pressure thereto and cause the same to expand laterally into sealing engagement with said casing and tubing head, a detent for holding said ram against retrograde.

movement away from said packing body, said ram 4comprising a split ring of a resilient material having an outer diameter when uncompressed which is greater than the inner diameter of said counterbore, and said detent comprising mating ratchet teeth on the outer surface of said ram and the inner surface of said counterbore.

7. In combination with a well casing, casing head and tubing head in which the casing head and tubing head are secured and sealed to each other and surround the upper end of said casing in spaced relation thereto and said tubing head is provided with a counterbore extending upwardly from its lower end and surrounding said casing, an annular packing body within said counterbore and surrounding said casing, a support ring extending upwardly from within said casing head land engaging said packing body to support the same against downward movement, an annular ram above said packing body and movable downwardly to apply pressure thereto and cause the same to expand laterally into sealing engagement with said casing and tubing head, a detent for holding said ram against retrograde movement away from said packing body, said detent comprising a pair of wedge shaped split rings in wedging engagement with each other between said casing and the wall of said counterbore and one of said rings being in engagement with said ram and adapted to be forced into tighter wedging engagement with the other ring upon movement of said ram away from said packing body.

8. In combination with a well casing, casing head and tubing head in which the casing head and tubing head are secured and sealed to each other and surround the upper end of said casing in spaced relation thereto and said tubing head is provided with a counterbore extending upwardly from its lower end and surrounding said casing, an annular packing body within said counterbore and surrounding said casing, a support ring extending upwardly from within said Casing head and engaging said packing body to support the same against downward movement, an 'annular ram above said packing body and movable downwardly to apply .pressure thereto and cause the same to expand laterally into sealing engagement With said casing and tubing head, a detent for holding said ram against retrograde movement away from said packing body, said detent comprising a pair of wedge shaped split rings in wedging engagement with each other between said casing and the wall of said counterbore and one of said rings being in engagement with said ram and adapted to be forced into tighter wedging engagement with the other ring upon movement of said ram away from said packing body, and said rings having upwardly inclined gripping teeth in engagement with the wall of said counterbore and the outside of said casing respectively.

MADDEN T. WORKS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,800,085 Kroeger Apr. 7, 1931 1,867,321 McEvoy July 12, 1932 1,887,865 Archer Nov. 15, 1932 2,312,476 Penick Mar. 2, 1943 I2,313,308 Allen Mar. 9, 1943 

